0:00:05 > 0:00:08# If you've got a question and you don't know where to go
0:00:08 > 0:00:11# Ask Nina for some help Cos she's got a science show
0:00:11 > 0:00:14# She makes sense of her senses While helping all her fans
0:00:14 > 0:00:17# By doing her experiments with potions and with bangs
0:00:17 > 0:00:19- # Touch your tongue - Tongue!
0:00:19 > 0:00:20- # Fingers - Fingers!
0:00:20 > 0:00:23- # Eyes.- Eyes! - Ears.- Ears!- Nose.- Nose!
0:00:23 > 0:00:26# Nina and the Neurons find out what you need to know
0:00:26 > 0:00:29# Nina and the Neurons find out what you need to know
0:00:29 > 0:00:32# Luke, he helps us with our eyes and Felix with our touch
0:00:32 > 0:00:35# Ollie sniffs out smells And Belle, she hears so much
0:00:35 > 0:00:38# Bud is Ollie's brother He helps us with our taste
0:00:38 > 0:00:41# They're Nina's little neurons And they're coming to your place!
0:00:41 > 0:00:43- # Touch your tongue - Tongue!
0:00:43 > 0:00:44- # Fingers - Fingers!
0:00:44 > 0:00:48- # Eyes.- Eyes! - Ears.- Ears!- Nose.- Nose!
0:00:48 > 0:00:50# Nina and the Neurons find out what you need to know
0:00:50 > 0:00:53# Nina and the Neurons find out what you need to know
0:00:53 > 0:00:55# Oh yeah! #
0:00:56 > 0:00:57Oh, hello.
0:00:57 > 0:01:02I'm using my thermometer to measure how hot these beakers are
0:01:02 > 0:01:06to find out which of these materials will keep my tea hot
0:01:06 > 0:01:09because every time I try and have a cup of tea...
0:01:09 > 0:01:11BLEEP! BLEEP!
0:01:11 > 0:01:12..that happens.
0:01:12 > 0:01:17I hear a beep, I see a flash. I wonder what they're going to ask.
0:01:19 > 0:01:21ALL: Hi, Nina!
0:01:21 > 0:01:23Hello.
0:01:23 > 0:01:25We've got a question for you.
0:01:25 > 0:01:28Why does chocolate melt in our hands?
0:01:28 > 0:01:30What a fantastic question!
0:01:30 > 0:01:32Why does chocolate melt in our hands?
0:01:32 > 0:01:36Come to the lab and do some experiments to investigate.
0:01:36 > 0:01:40- ALL: See you soon, Nina!- Bye!
0:01:40 > 0:01:44I'll need some help to answer this one and I know just who to ask.
0:01:44 > 0:01:47OK, neurons. Time to get to work.
0:02:03 > 0:02:06ALL: Neurons at the ready, Nina.
0:02:06 > 0:02:10OK, today's question is why does chocolate melt in our hands?
0:02:10 > 0:02:14Which neuron do you think will help us find the answer?
0:02:14 > 0:02:16- Me! Me!- Oh, me!- Me!
0:02:16 > 0:02:19Will it be fabulous Felix?
0:02:19 > 0:02:22I can help so very much if you need the sense of touch.
0:02:22 > 0:02:25Will it be beautiful Belle?
0:02:25 > 0:02:29I send messages to brain from ear. If there's a sound, I'll help you hear.
0:02:29 > 0:02:31Will it be lovely Luke?
0:02:31 > 0:02:34For looking and seeing, day or night,
0:02:34 > 0:02:36I'll help you with your sense of sight.
0:02:36 > 0:02:38Will it be awesome Ollie?
0:02:38 > 0:02:41If it's whiffy, but you can't tell,
0:02:41 > 0:02:43my messages help your sense of smell.
0:02:43 > 0:02:47- Or will it be baby Bud? - Sour, salty, bitter or sweet,
0:02:47 > 0:02:49I'm your taste buddy when you eat.
0:02:51 > 0:02:53It's Bud and Ollie!
0:02:53 > 0:02:57CHEERING
0:02:57 > 0:03:00Go, Ollie! Go, Bud! Go, Ollie! Go, Bud!
0:03:00 > 0:03:02Go, Ollie! Go, Bud!
0:03:02 > 0:03:05Yippee! It's you and me, sis.
0:03:05 > 0:03:08Stand by for a taste and smellathon.
0:03:08 > 0:03:12Today's question is why does chocolate melt in our hands?
0:03:12 > 0:03:15Chocolate is something we taste and smell,
0:03:15 > 0:03:17so I chose Bud and Ollie to help us.
0:03:17 > 0:03:22I'd better get the lab ready before the experimenters arrive.
0:03:22 > 0:03:25Bronte likes history,
0:03:25 > 0:03:26Ruby collects shells,
0:03:26 > 0:03:28and Sakshi loves dressing up,
0:03:28 > 0:03:32but they all want to know about melting chocolate,
0:03:32 > 0:03:38so today, Bronte, Ruby and Sakshi become the experimenters!
0:03:38 > 0:03:40ALL: Hi, Nina!
0:03:40 > 0:03:43Come on in! Welcome to my science lab.
0:03:43 > 0:03:45It's lovely to see you all.
0:03:45 > 0:03:49Your question is why does chocolate melt in our hands?
0:03:49 > 0:03:50Why do you want to know?
0:03:50 > 0:03:54When I touch chocolate, it melts in my hands.
0:03:54 > 0:03:59- Sometimes it comes on my clothes. - And mine.
0:03:59 > 0:04:01Oh, no! That happens to me too!
0:04:01 > 0:04:04I think we have some messy investigating ahead of us.
0:04:04 > 0:04:08For our first experiment, we'll use our senses.
0:04:08 > 0:04:12ALL: Whoop-woo! A senses experiment! We're ready, Nina!
0:04:12 > 0:04:14OK, guys. We're going to pick up
0:04:14 > 0:04:17a piece of chocolate and hold it in our hands
0:04:17 > 0:04:20to see if we can melt it, OK?
0:04:20 > 0:04:21But no eating!
0:04:23 > 0:04:27And hold it in your hand.
0:04:27 > 0:04:29Mm-mm! Chocolate!
0:04:31 > 0:04:34- What does the chocolate feel like?- Gooey.
0:04:34 > 0:04:38The chocolate is changing from being hard to being runny,
0:04:38 > 0:04:40almost like a liquid.
0:04:40 > 0:04:44When something changes from a hard solid to a runny liquid,
0:04:44 > 0:04:45we say it's melting.
0:04:45 > 0:04:48Does it still smell like chocolate?
0:04:48 > 0:04:51- Yes.- Yes.- Yes.
0:04:51 > 0:04:56So melted chocolate still smells and tastes like chocolate.
0:04:56 > 0:05:00Hey! How do we know it still tastes like chocolate?
0:05:00 > 0:05:02Oh, well, that's a good point, Bud.
0:05:02 > 0:05:07I suppose, for scientific research, maybe we should taste the chocolate.
0:05:07 > 0:05:09Yay!
0:05:10 > 0:05:15Mm! Oh, it definitely tastes like chocolate. What do you think?
0:05:16 > 0:05:19I'll take that as a yes. Ha-ha!
0:05:19 > 0:05:22We've learned that melted chocolate
0:05:22 > 0:05:25is the same as hard chocolate, just runnier.
0:05:25 > 0:05:29Oh! I think we'd better get washed before the next experiment.
0:05:31 > 0:05:33We know chocolate melts in our hands.
0:05:33 > 0:05:36What else can you think of that melts?
0:05:36 > 0:05:39Snow and ice lollies.
0:05:39 > 0:05:42- Ice cubes.- Ice cream.
0:05:42 > 0:05:46Yes. Oh, now, here's the wrapper from the chocolate earlier.
0:05:46 > 0:05:49What do you think that's made of?
0:05:49 > 0:05:51- Tin?- Silver?
0:05:51 > 0:05:55Yeah, it's a type of metal - really, really thin metal.
0:05:55 > 0:06:00- You couldn't melt this in your hand, could you?- ALL: No!
0:06:00 > 0:06:06- And why not?- Cos metal doesn't melt in your hands.
0:06:06 > 0:06:08I was hoping you might say that.
0:06:08 > 0:06:11I have something that might surprise you,
0:06:11 > 0:06:14so goggles on and follow me.
0:06:14 > 0:06:19What's Nina talking about? We can't melt metal in our hands.
0:06:19 > 0:06:22Oh, maybe Nina's got superpowers!
0:06:22 > 0:06:28No, Bud, I don't have superpowers, but I do have a very special metal
0:06:28 > 0:06:31that you guys won't ever have seen before.
0:06:31 > 0:06:34This metal in here is called mercury.
0:06:34 > 0:06:39We've got to be very careful with mercury because it's bad for us.
0:06:39 > 0:06:42I don't want the glass to break.
0:06:42 > 0:06:44I've been keeping it really cold.
0:06:44 > 0:06:47Let's see what happens when it warms up again.
0:06:47 > 0:06:50What does the mercury look like now?
0:06:50 > 0:06:52- Hard.- Yes, it's quite hard, isn't it?
0:06:52 > 0:06:56- Silver.- Yeah, it's a lovely silvery colour.
0:06:56 > 0:06:57Look!
0:06:57 > 0:07:01It's starting to melt. Can you see that?
0:07:01 > 0:07:03- Yeah.- Yeah.
0:07:03 > 0:07:04It's like silvery water.
0:07:04 > 0:07:09- LUKE:- That is way cool!- Mercury's different from most metals.
0:07:09 > 0:07:12It melts easily, even at room temperature.
0:07:12 > 0:07:15What is temperature, Nina?
0:07:15 > 0:07:19Temperature means how hot or cold something is,
0:07:19 > 0:07:22so room temperature means as warm as a room.
0:07:22 > 0:07:26This experiment shows a room is warm enough to melt mercury.
0:07:26 > 0:07:29We need to take a trip to somewhere really hot,
0:07:29 > 0:07:34- so let's go, experimenters, and find out more about melting!- Yay!
0:07:39 > 0:07:40Here we go!
0:07:40 > 0:07:43I can't wait to see where we'll end up today.
0:07:43 > 0:07:49- Nina said we're going somewhere hot. Maybe we're going...- To the seaside!
0:07:49 > 0:07:54- Pack your swimming trunks, Felix! - It doesn't smell like the seaside.
0:07:59 > 0:08:02Let me just check where we're meant to be.
0:08:02 > 0:08:04Excuse me.
0:08:04 > 0:08:06Em, excuse me.
0:08:06 > 0:08:10- She's not saying very much, is she? - She's a statue, Nina!
0:08:10 > 0:08:16Oh! Oh, so she is. Silly me! What do you think she's made of?
0:08:16 > 0:08:18Some kind of metal?
0:08:18 > 0:08:23That's right! This statue is made of a type of metal called bronze.
0:08:23 > 0:08:25To make the statue, the bronze is melted.
0:08:25 > 0:08:28Follow me, experimenters.
0:08:41 > 0:08:44Although they're both metals,
0:08:44 > 0:08:47bronze is not like the mercury we saw in my lab.
0:08:47 > 0:08:51Bronze needs to be very, very, very hot to melt,
0:08:51 > 0:08:54so these bronze bars need to be put into
0:08:54 > 0:08:58a special sort of oven called a furnace. It's incredibly hot!
0:08:58 > 0:09:01To be safe, we're standing well back.
0:09:08 > 0:09:13The solid bronze bars have melted in the red-hot furnace
0:09:13 > 0:09:15and turned into runny liquid bronze.
0:09:25 > 0:09:28One, two, three - up!
0:09:31 > 0:09:34Why are the men carrying it like that, Nina?
0:09:34 > 0:09:38The melted bronze is really, really hot
0:09:38 > 0:09:42so they're carrying it on those long rods so they won't get burnt.
0:09:42 > 0:09:46They're pouring the hot, melted bronze into a mould,
0:09:46 > 0:09:48a bit like when we make jelly.
0:09:50 > 0:09:53The mould is the shape the statue will be.
0:09:53 > 0:09:56When the bronze cools down, it will become hard again
0:09:56 > 0:10:00and they'll have a hard bronze statue like our silent friend.
0:10:00 > 0:10:04We've discovered some things, like bronze,
0:10:04 > 0:10:06need to be very, very hot to melt,
0:10:06 > 0:10:10but we still don't know why chocolate melts in our hands.
0:10:10 > 0:10:12We need to do one final experiment.
0:10:12 > 0:10:15Come on, guys, let's go back to the lab.
0:10:16 > 0:10:19We know chocolate melts in our hands.
0:10:19 > 0:10:22Let's get experimenting to find out why.
0:10:22 > 0:10:24- ALL: Yeah!- OK.
0:10:24 > 0:10:27Bronte, you have three candles in front of you.
0:10:27 > 0:10:32Ruby has three pieces of butter. Sakshi, you have the chocolate.
0:10:32 > 0:10:35Take one of your experiment items
0:10:35 > 0:10:38and sit it in the middle of this mat.
0:10:38 > 0:10:42Next, we'll place our second item onto this metal plate.
0:10:42 > 0:10:45The metal plate is hotter than room temperature
0:10:45 > 0:10:49because it's sitting on hot water, so I'll be very careful.
0:10:49 > 0:10:52Hot water can burn, you know.
0:10:52 > 0:10:54Thank you and a piece of chocolate
0:10:54 > 0:10:56and a candle.
0:10:57 > 0:10:58Great.
0:10:58 > 0:11:02And finally, can you please pick up your last item,
0:11:02 > 0:11:06hold it in your hand and I'm going to see if we can melt it.
0:11:06 > 0:11:11Let's have a look and see what's happening on the metal plate.
0:11:11 > 0:11:12I'll use Nina-cam.
0:11:12 > 0:11:15Oh! It's all runny now!
0:11:15 > 0:11:19So the metal plate was hot enough to melt everything.
0:11:19 > 0:11:21How are your hands doing?
0:11:21 > 0:11:23Oh! Ooh!
0:11:23 > 0:11:26It's getting a bit messy.
0:11:26 > 0:11:28- How's your candle, Bronte?- Hard.
0:11:28 > 0:11:31Hmm. So the heat from your hands
0:11:31 > 0:11:34was warm enough to melt butter and chocolate,
0:11:34 > 0:11:35but not a candle.
0:11:35 > 0:11:37What's happening on the mat?
0:11:37 > 0:11:42- My butter's melting.- It's getting all gooey round the bottom,
0:11:42 > 0:11:45but the chocolate and candle are still hard.
0:11:45 > 0:11:50So room temperature is only warm enough to melt the butter.
0:11:50 > 0:11:54Your hands are warm enough to melt butter and chocolate,
0:11:54 > 0:11:59but the plate over the hot water is hot enough to melt all three.
0:11:59 > 0:12:01# Nina and the Neurons. #
0:12:01 > 0:12:05Your question was why does chocolate melt in our hands
0:12:05 > 0:12:07and I think we've answered it.
0:12:07 > 0:12:09We discovered that when things melt,
0:12:09 > 0:12:12they change from a hard solid to a runny liquid
0:12:12 > 0:12:16and most things melt - even hard metals like bronze.
0:12:16 > 0:12:19Different things melt at different temperatures.
0:12:19 > 0:12:23Some things melt at room temperature, like butter,
0:12:23 > 0:12:27but other things, like chocolate, need more heat to melt.
0:12:27 > 0:12:32Our hands are warmer than the room, warm enough to melt chocolate.
0:12:32 > 0:12:37- I hope that's answered your question.- ALL: Thanks, Nina. Bye!
0:12:37 > 0:12:39Bye!
0:12:43 > 0:12:46If you want to know more about the science all around us,
0:12:46 > 0:12:50go to the Nina section on the CBeebies website. Have fun!
0:12:54 > 0:12:55Lab coat on, Nina?
0:12:55 > 0:12:57Lab coat on, Ollie.
0:12:57 > 0:12:59Safety gloves on, Nina?
0:12:59 > 0:13:01Safety gloves on, Felix.
0:13:01 > 0:13:03And don't forget your goggles, Nina.
0:13:03 > 0:13:07Goggles are on, Luke. I think we're ready!
0:13:08 > 0:13:10# We do experiments in the lab
0:13:10 > 0:13:14- # In the lab - Shooby-dooby in the lab
0:13:14 > 0:13:16# Bubbling experiments in the lab
0:13:16 > 0:13:20- # In the lab! - Go, Nina, in the lab
0:13:20 > 0:13:23# Fizzing and popping Steam and smoke
0:13:23 > 0:13:26# We need protection Don't we, folks?
0:13:26 > 0:13:30# We always put our safety first
0:13:30 > 0:13:32# Shooby-dooby-dooby-dooby
0:13:32 > 0:13:34# We do experiments in the lab
0:13:34 > 0:13:35# In the lab!
0:13:35 > 0:13:36# Go, Nina! #
0:13:36 > 0:13:38It's been a marvellous day.
0:13:38 > 0:13:42The melted chocolate felt all gooey and sticky.
0:13:42 > 0:13:44I've had a fabby day!
0:13:44 > 0:13:48The chocolate tasted just as yummy melted.
0:13:48 > 0:13:50I've had a brilliant day,
0:13:50 > 0:13:55hearing all about how statues are made by melting metal.
0:13:55 > 0:13:57I really enjoyed myself today.
0:13:57 > 0:14:02The butter melted really quickly and smelled delicious.
0:14:02 > 0:14:05Our day's been bursting with sensational experiments.
0:14:05 > 0:14:07I hope you enjoyed it. Bye!
0:14:07 > 0:14:09ALL: Bye!
0:14:09 > 0:14:12E-mail subtitling@bbc.co.uk